Electric can opener

ABSTRACT

An electric can opener provided with a cutter base held at its can opening position by the reaction force exerted on a cutter carried by said cutter base, in which the operation of the can opener is initiated by pushing a start push button and interrupted by lightly pushing a release push button, a can to be opened being still mounted on the can opener while the removal of the can from the can opener becomes possible by heavily pushing the release push button at the time of completion or interruption of the can opening operation.

United States Patent [1 1 Yamamoto 1 1 Oct. 2, 1973 [541 ELECTRIC CAN OPENER 2,994,953 8/1961 Abcrcr 30/4 R 3,611,565 10/1971 McLean... 30/4 R [75] Invent Nagoya' Japan 3,706,135 12/1972 Fukunnga 30/4 R [73] Assignee: Kabushiki Kaisha Aichidenkikosakusho, Aichi-ken, Primary Examine r0thell M. Simpson Japan Assistant Examiner-Gary L. Smith Filed: J 1971 Attorney-William C. Linton et a1.

[21] Appl. No.: 154,495 57 ABSTRACT An electric can opener provided with a cutter base held [30] Foreign Application Priority Data at its can opening position by the reaction force exerted Apr. 1, 1971 Japan 46/19801 on a cutter carried y Said cutter base, in which t p eration of the can opener is initiated by pushing a start [52] U.S. Cl. 30/4 R, 30/9 p button and n r p y ligh ly pushing a release [51] B671) 7/38 push button, a can to be opened being still mounted on [58] Field of Search 30/4 R, 8, 8.5, 9 the can p r while h em v l of the can from the can opener becomes possible by heavily pushing the re- [56] Referen e Cited lease push button atthe time of completion or interrup- UNITED STATES PATENTS tion of the can opening operation.

2,897,589 8/1959 Bodle 30/4 R 3 Claims, 13 Drawing Figures lial Pmminwz 3.152.044

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FIG.'I1.

ATTORNEY ELECTRIC CAN OPENER This invention relates to an electric can opcrer which automatically severs a can top along the inside of the end stem of a can, feeding the end stem by a feeder wheel driven by an electric motor and more particularly to an electric can opener in which by pushing a push button, a cutter base carrying a cutter and pivoted on a housing is lowered to make the cutter contact the can top and the electric motor begins to rotate at the same time, then the cutter is pulled in to pierce the can top as the result of the driving force applied to the feeder wheel, the cutter is maintained at this piercing position (referred to as the opening position hereafter) during the can opening operation, on finishing of the opening operation the electric motor is automatically stopped, the opened can is held not to fall off, the separated ean top is attracted by an attracting device, and by pushing another push button, the opened can becomes removable while by said operation on another push button, the can opening operation may be interrupted if necessary and it becomes possible to remove the partly opened can. The present invention relates also to an electric can opener in which by bushing one push button instead of two push buttons described, the opening operation of a can, the automatic stop of it and the removal of the can are effectuated.

In a conventinal electric can opener device, a cutter lever carrying a cutter and pivoted on a housing at one end portion is lowered by an operator to make the cutter pierce the can top, the driving by an electric motor is initiated at the same time, the cutter is maintained at this position (the opening position) by a hand of the operator during the opening operation, and after the opening operation, the operator raises the cutter lever with his hand touching the can being rotated by the feed wheel, deenergizes the electricmotor at the same time and removes the opened can from the can opener. Thus the cutter lever, which requires a considerable lenght for easy operation because the operator must pierce the cutter into the can top as apreparatory operation, extends largely from the housing whereby spoiling the overall design of the can opener making packages for transportation very bulky and requiring large space in order to be kept at homes.

An object of the present invention is to provide an electric can opener in which the movement of a cutter base is started by pushing a push button in stead of lowering the conventional cutter lever, thereby initiating the opening operation, the cutter is returned some what from the opening position automatically after the completion of the opening operation, theelectric motor is deenergized, the cutter is held temporally at a position (referred to a holding position hereafter) where the opened can is held .by thecutter in cooperation with a can receiver formed on a front vertical member of the housing and the cutter is retired from the holding position by another operation in order to make the opened can removable from the can opener body.

Another object of the present invention is to provide an electric can opener in which an electric motor is energized by pushing a push button, and a cutter in contact with a can top is forced to pierce into the can top by the reaction force exerted on the cutter from a feed wheel, thereby making it possible automatically to intiate the opening operation with a light touch on a push button without requiring any large force for an operator to exert on the conventional cutter lever.

Still another object of the present invention is not only to make the overall design ofa can opener beautiful without using a member extending from a housing such as the cutter lever but also to provide a small and compact can opener requiring less packages and less space for keeping.

The above and other objects and fearures of the present invention will become apparent from the accompanying claims and the following detailed description taken in conjunction with the drawings in which:

FIG. 1 is a front elevational view of an electric can opener,

FIG. 2 is a plane view of the can opener,

FIG. 3 is a longitudinal sectional view taken along a line 3-3 in FIG. 1,

FIG. 4 is a rear elevational view with the rear member of a housing taken away,

FIG. 5 is a front elevational view of movable members,

FIG. 6 is a longitudinal sectional view of a release rod,

FIG. 7 is a sectional view taken along a line 7-7 in FIG. 1,

FIGS. 8-10 are views of main parts of the can opener shown in FIG. 4 for describing operations,

FIG. 11 is a sectional fragmental view of a release means,

FIG. 12 is a rear view showing main portions of a different embodiment of the release means and FIG. 13 is a sectional view of main portions viewed from the left hand side of FIG. 12.

Referring to figures, in a housing 1 are mounted an electric motor 2 and a reduction gear assembly 3 which isconnected between the rotor shaft of the electric motor 2 and a driving shaft 3' in order to give the latter suitable revolutions per minute. The driving shaft 3' extends forwardly from a front member 1 forming part of the housing 1 through a bearing member 4 formed as an enlarged portion on the internal surface of the front member 1' and a toothed feeder wheel 5 is attached on the extending end of the driving shaft 3'. Above the shaft 3, a substantially rectangular cutter base 6 is pivoted on the front member 1 by its support ing stud 7 which is received rotatably in a bearing member 8 extending from the internal surface of the front member 1. The tip portion of the stud 7 passing through the bearing member 8 is provided with an annular groove 7 which engages the lower edge of an elongated hole 9 bored through a vertically movable locking plate 9 to prevent the further axial displacement of the stud 7. The locking plate 9 is biased towards its locking position by a spring 10 and the engagement between the edgeof the elongated hole 9' and the annular groove 7' is released by pushing down a cutter base removing push button 11 which is secured on the locking plate 9 and protrudes through the upper member of the housing 1 while the cutter base 6 is pushed away from the housing 1 by the force of a plate spring 12 which is fixed at its one end on the internal surface of the housing and pushes the stud 7 always towards the front member 1'. In an axial hole 6' bored obliquely downwards through the lower portion of the cutter base 6 is received a shaft 13 carrying a circular cutter l3 rotatably and the cutter 13 is positioned on the shaft 13 in such a manner that the edge of the cutter 13 approaches to the front peripheral portion of the feeder wheel 5 and pierces a can top 41 of a can 40 near an end stem 40, proceeding to sever the rotating can top. Thus, the shaft 13 is mounted in such a oblique direction against the front member 1' that the edge of the cutter 13, directing in an obliquely downward direction, can hold the can 40 cooperating with the feeder wheel. A clock wise moment around the stud 7 in FIG. 1, which results from the driving force for the feeder wheel 5, maintains the cutter base 6 at the opening position. In front of the cutter 13, a permanent magnet 14 to catch the can top out off from the can is suspended from the upper portion of the cutter base 6 by an arm 14'. A projection 60 auxiliarily to hold the can pierced into by the cutter 13 is secured on the cutter base 6 behind the cutter l3 and another projection 6d for the same purpose is disposed forwardly of the housing 1 obliquely above the driving shaft 3. Further, on the rear surface of the cutter base, as a coupling member an arc-shaped gear with its center of curvature coinciding with the stud 7 is formed integrally and is adapted to protrude into the housing through an areshaped recess 15 bored through the front member 1' when the cutter base 6 is mounted to the housing. Thus, the cutter base 6 is rotable around the stud 7 within a certain angle. Next, in the housing 1, a first movable member 17 and a second one 18 are inserted slidably in the vertical direction in one of two guide openings bored through the horizontal arm of a L-shaped fitting 16 and in the other of said guide openings is inserted slidably a release rod 19 to release the engagement of the first movable members 17 with a holding piece to be described later. Elongated holes 17' and 18 are bored through the members 17 and 18 respectively and through these holes, a guide screw 20 is threadably adapted in the front member 1' in order to guide and stabilize vertical movements of the members 17 and 18. The upper portion of one side of the first movable member 17 is provided with a rack 21, as a coupled member, which is in mesh with the arc-shaped gear 15, thereby transforming its vertial linear movement into the rotation of the cutter base. On the other side of the member 17 is provided a shoulder portion 22 as an engaging means and the central portion of the member 17 is provided with a U-shaped slot where a coil spring 24 is adapted, the lower end of said 'coil spring being supported by the L-shaped fitting 16. The second movable member 18 is provided with a closer 25 having a tapered surface at the lower end, a shoulder portion 18a at the upper portion, a start push button 26 extending through the top member of the housing 1 at a certain distance from the shoulder portion 18a and an opening 18" at the central portion in order not to be obstructive to the mounting of said coil spring 24. The upper end of the member 17 and the push button 26 are connected by a coil, spring 27 inserted between them. When the push button 26 is lowered, the member 17 moves together with the second movable member 18, rotating the cutter base 6 but when the cutter 13 pierces into the can top and the cutter base suffers from a reaction force against its rotation, the first movable member 17 ceases to move downwards and only the second movable member 18 is lowered further by a certain distance. v

Next, a release means for the movable members 17 and 18 is described. Between a spring seat 19 formed at the lower portion of the release rod 19 and the L- shaped fitting 16, a compression spring 28 is inserted and the upper end of the release rod is provided with a release push button 29 protruding through the top member of the housing. This push button is made partly hollow. A guide screw 30 is threadably secured to the front member 1' through an elongated hole 19" bored through the release rod 19 in order to prevent the rod 19 from rising unnecessarily and to stabilize its vertical movement. A holding piece 31 shown as a holding means is pivotally supported on the front member 1', crossing the rod 19 and the free end of the piece 31, keeping contact with the side of the member 17 provided with the shoulder portion 22, is biased towards said side of the member 17. At the side facing the holding piece 31, the release rod 19 is provided with a projection 32 for releasing the engagement between the member 17 and the holding piece 31 and to the lower end of the rod 19 a clearer 33 with a tapered surface is secured as a means to stop the electric motor during a can opening operation. Between the closer 25 attached to the lower end of the member 18 and this clearer 33 are disposed a movable piece 34 made of resiliant material such as copper plate and another resilient movable piece 35 bending towards the tapered surface of the closer 25 and on the confronting sides of the upper portions of the pieces 34 and 35 are attached a pair of electrical contacts 36 and 37. The relative position of the closer 25 and the bending movable piece 35 is such that by pushing down the start push button 26 the movable members 17 and 18 are lowered to make the tapered surface of the closer 25 be in contact with the bending movable piece 35 and the latter be pushed against the other movable piece 34 but when the first movable member 17 is lowered to operate the rack 21 and the cutter base 6 as far as the cutter 13 contacts with the can top, the electrical contacts 36 and 37 do not yet contact with each other and after the stop of the cutter base 6 by the resisting force exterted on it from the can top the bending movable piece 35 is pushed towards the piece 34 by the closer 25 to establish the contact between the electrical contacts 36 and 37 while the second movable member 18 lowered to compress the coil spring 27 by the distance between the upper end of the member 17 and the push button 26, the electric motor 2 thus being energized through the closed contacts 36 and 37. The engagement between the shoulder portion 22 of the first movable member 17 and the holding piece 31, which takes place by the time when the upper end of the first movable member 17 is lowered by the cutter base 6 actuated by the reaction force transmitted through the cutter 13 after energization of the electric motor 2 until said upper end coincides with the shoulder portion 18a of the second movable member already lowered by the distance between the upper end of the member 17 and the push button 26 prevents the first movable member 17 from rising. To the linear movable piece 34 is attached a rectangular engage frame 38 through which the clearer 33 is slidably inserted when the release rod 19 is lowered. During the process of this insertion, the tapered surface of the clearer 33 is in position to pull the movable piece 34 away from the bending movable member 35, thereby disconnecting the contact 36 from the contact 37 to deenergize the electric motor 2. When lowered down further, the release rod 19 is in position to return the movable members 17 and 18 by making the projection 32 push away the holding piece 31 to release the engagement between said piece and the shoulder portion 22. On the outer surface of the front member 1 is provided a can receiver 39 for supporting the can to be opened.

The operation of the electric can opener described above is as follows. Firstly, the cylindrical wall of the can to be opened is made in contact with the can receiver 39. Then, the loweredge of the can end stem 40' is kept in contact with the toothed peripheral portion of the feeder wheel 5 and the push button 26 is pushed down to lower the movable member 17, the force exerted by an operator being transmitted to the member 17 through the spring 27. Consequently, the arc-shaped gear being in mesh with the rack 21 rotates together with the cutter base 6 to make the edge of the cutter l3 touch the can top 41. In this situation, the holding piece 31 has engaged the shoulder portion 22 to prevent the upward return movement of the member 17 and also the movable member 18 is kept at its lower position after it was moved with force by the member 17. However, the contacts 36 and 37 are not yet closed. When the push button 26 is lowered further, the cutter 13 is pressed strongly on the can top 41 without moving downward further and the spring 19' is conpressed, while the movable member 18 is lowered, making the closer push the bending movable piece to close contacts 36 and 37 as shown in FIG. 8. Thus, the driving shaft 3 is actuated by the electric motor 2 to feed the can and the cutter base 6 is rotated so as to pierce the cutter 13 into the can top 41 as the result of the force which it exterts on the cutter 13 in contact with the can top 41 in a direction shown by an arrow 5a. Thus, the member 17 is lowered as the result of the movement of the rack 21 and the arcshaped gear 15 and consequently also the member 18 is kept at a position to close the contacts 36 and 37. (c.f. FIG. 9). Thereafter, the cutter 13, being kept at its opening position, proceeds to sever the can top 41 fed by the feeder wheel 5. When the opening operation is finished, the force exterted on the cutter 13 from the can top 41 disappears and the movable member 17 is raised some what together with the spring 27 and the push button 26 until said member 17 is stopped by the engagement between the shoulder portion 22 and the holding piece 31. (c.f. FIG. 10). At the same time, also the movable member 18 is raised by a corresponding distance, disconnecting contacts 36 and 37 to stop the electric motor 2. At this instance, the cylindrical surface of the can is still in contact with the can receiver 39 and the cutter 13 touches the inner side of the end stem 40', the can 40 being held forwardly of the front member 1'. In order to remove the can 40 from the can opener, the release push button 29 is pushed down to lower the projection 32, which detaches in turn the holding piece 31 from the shoulder portion 22. Then the push button 26 and movable members 17 and 18 are returned to their positions before the can opening operation and the can 40is removable from the can opener body. Halfway in the can opening operation, for example, when the can opener is stopped the remaining part of the periphery of the can top is not severed, the contacts 36 and 37 can be opened by pushing the release push button 29 lightly to lower the clearer 33 into the frame 38 and to distort the movable piece 34. By this operation, the reaction force exerted on the cutter l3 dissapears and the member 17 rises. In this case, if the release rod 19 is not lowered so far as its projection 32 releases the engagement between the holding piece 31 and the shoulder portion 22, the movable members 17 and 18 are at the same position as they are when the opening operation is just finished. The can with its incompletely severed top can be removed by pushing the push button 29 further. When the opening operation is to proceed after an interruption, the closer 25 is lowered to close the contacts 36 and 37 by operating the start push button 26 and as described before, the cutter 13 is automatically pulled in to its opening position again by the force exerting on the cutter 13 from the can top 41. The opening operation continues until said force exerting on the cutter l3 disappears.

Referring to FIGS. 12 and 13, is described an embodiment for effectuating said starting and releasing operations with use of a single push button. As for the description of a starting mechanism A and members associated with it, those parts which are considered constructionally similar to those already described are given same reference numerals as before in order to omit repeated descriptions. A holding mechanism H is described. An intermittently rotatable member 51 is provided with an arbitrary number, for example eight, of nail portions 51 and is mounted rotatably on the front member 1 by a square pin 53 provided with a head to prevent the falling off of it. On the rear surface of the intermittently rotatable member 51 are formed projections 51" as many as a half number of the nail portions 51' and are disengageably adapted in complementary concave portions formed on one side of a loosely coupled member 54 through which the square shaped portion of the pin 53 is loosely inserted. The loosely coupled member 54 is biased towards the member 18 usually by a spring 55. As another embodiment of the release mechanism, a release member 56 is pivoted on the second movable member 18 by a pin 57 and is biased usually by a spring 58 in such a manner that a pin 59 attached to the second member 18 contacts with one edge of an elongated hole 56' bored through the release member 56 as best seen in FIG. 12. When the start push button 26 is pushed down in the situation as shown in FIGS. 12 and 13, the release member 56 touches one of the nail portions 51' to rotate the member 51 by one pitch, the projections 51" on the member 51v are fit in the concave portions formed on the loosely coupled member 54 and a holding projection 60 formed on the member 54 is inserted in an elongated hole 59' bored through the first movable member 17 preventing the first movable member 17 from rising freely. The release member 56 rises sliding on the pheriphery of the'member 51 when thesecond movable member 18 rises. Next, the member 51 is rotated in the same manner as described before by pushing down the push button 26 again thereby causing the projections 51" to get out from said complementary concave portions. Thus, the holding piece 60 is pulled out from the elongated hole 59 and the first removable member 17 becomes again able to rise freely. Thereafter, the opening of the can top can be possible repeatedly if the operation described above is repeated.

As is understood from the foreging descriptions, this invention has an advantage that the force to push down the start push button intially can be small and a light touch on the push button can intiate a can opening process because the electric motor is started by pushing down the start push button and then the cutter base 6 is rotated by the force exerting on the cutter 13 from the can top 41 to pull in the cutter 13 to its opening position when the cutter pierces into the can top. Further,

as the can opener according to the present invention includes the first movable member 17 operated by pushing the start push button 26, a cutter base 6 carrying the cutter 13 connected to the movable member 17, a holding means to hold the member 17 after it is pushed down, the release means for releasing the member 17 and the contacts 36 and 37, which can be closed by the closer carried by the second movable member 18 taken with by the member 17 and the cutter 13 returns by a certain distance from its opening position when the reaction force on the cutter 13 disappears, holding the can at the inner side of the end stem 40, the can 40 is severed completely even if the push button 26 is left as it is after the start of the electric motor and the can 40 is held securely on the front member thereafter, being easily removable by operating the release means. Further, as the contacts 36 and 37 can be opened by operating the push button 29, it is a practical advantage to interrupt an opening operation by pushing the push button 29 when the opening operation is to be stopped. When the opening operation is to be reinitiated after an interruption, the opening operation can reinitiated by pushing the start push button 26.

It should be understood that although the present invention has been described with preferred embodiments, many changes and modifications are possible without departing from the scope of the present inven tion and accompanying claims.

What I claim is:

1. In an electric can opener comprising a housing having a front member with an opening, a driving shaft extending rotatably through a front member of said housing, a toothed feeder wheel attached to said driving shaft outside of said housing, a cutter base pivoted on said front member, a cutter mounted rotatably on said cutter base, the'pivot of said cutter base being positioned in such a manner that said cutter base can be held at its can opening position by a moment around said pivot resulting from the reaction force exerted on said cutter during a can opening operation and an electric motor with a reduction gear assembly for actuating said driving shaft, the combination therewith of a coupling member provided on the cutter base and extending through said front member opening, a first movable member behind said front member and provided with a coupled member and a shoulder portion, said coupling member and coupled member being operatively connected, an electric circuit with electrical contacts for energizing said electric motor, a second movable member having a closer at its lower end for operating said electrical contacts, and a start push button provided with a hollow portion, a deformable connection member connecting said start push button and said first movable member, said first and second movable members being displacable together in the absence of any resisting force on said first movable member, a holding piece engageable with said shoulder portion to prevent the complete return movement of said first movable member and a release rod for releasing the engagement between said shoulder portion and said holding piece, said electrical contacts being closed by said closer as the result of the movement of said second movable member after the contact of said cutter with a can top to be severed and being disconnected when said first movable member returns some what from its opening position as the result of the disaperance of said reaction force on said cutter base until said first movable member is stopped by said holding piece.

2. An electric can opener as described in claim 1 in which said coupling member and coupled member are an arc-shaped gear and a rack respectively.

3. An electric can opener as described in claim 1 in which said release rod is provided with a push button and a clearer for disconnecting said electrical contacts at an arbitrary instance. 

1. In an electric can opener comprising a housing having a front member with an opening, a driving shaft extending rotatably through a front member of said housing, a toothed feeder wheel attached to said driving Shaft outside of said housing, a cutter base pivoted on said front member, a cutter mounted rotatably on said cutter base, the pivot of said cutter base being positioned in such a manner that said cutter base can be held at its can opening position by a moment around said pivot resulting from the reaction force exerted on said cutter during a can opening operation and an electric motor with a reduction gear assembly for actuating said driving shaft, the combination therewith of a coupling member provided on the cutter base and extending through said front member opening, a first movable member behind said front member and provided with a coupled member and a shoulder portion, said coupling member and coupled member being operatively connected, an electric circuit with electrical contacts for energizing said electric motor, a second movable member having a closer at its lower end for operating said electrical contacts, and a start push button provided with a hollow portion, a deformable connection member connecting said start push button and said first movable member, said first and second movable members being displacable together in the absence of any resisting force on said first movable member, a holding piece engageable with said shoulder portion to prevent the complete return movement of said first movable member and a release rod for releasing the engagement between said shoulder portion and said holding piece, said electrical contacts being closed by said closer as the result of the movement of said second movable member after the contact of said cutter with a can top to be severed and being disconnected when said first movable member returns some what from its opening position as the result of the disaperance of said reaction force on said cutter base until said first movable member is stopped by said holding piece.
 2. An electric can opener as described in claim 1 in which said coupling member and coupled member are an arc-shaped gear and a rack respectively.
 3. An electric can opener as described in claim 1 in which said release rod is provided with a push button and a clearer for disconnecting said electrical contacts at an arbitrary instance. 